84' kdx 250 carb and parts help!

At it again.

Just acquired a kdx 250.

Needs a lot of love.

First off I took the carb off and cleaned it out (nasty!)

Through it back on-and noticed there's a few gas tube nipples with no lines coming from them.

Then put some gas in it and turned the petcock on-gas flowed in and then started coming out all the nipples with no tubes!!!

First thought is stuck float but it seems to be working?

Ill take it all back apart tomorrow and thoroughly clean everything.

Secondly-just for giggles I tried to fire it up.

Immediately I notice the exhaust leaking at the header to engine and it being EXTREMILY LOUD.

Then randomly it revved very high (while throttle still at idle)

Tried to hit the kill switch and it stayed runnin *panick mode*

Finally dies out.

Put it up for the night after that.

Some main questions

***carb gas line diagram??

***need new gas cap and carb rebuild kit. After googling I can't seem to find one available? All says discontinued. Any help finding these would be great!!!

Other then that I look forward to bringing this vintage back to life!

What I've found-the carb lines are "vents" and don't really need to be hooked up to run.

Double checked the kill switch and its functional (not sure why it wouldn't die that one day)

Lastly even after cleaning the carb completely out it seems the float is being picky.

Tried adjusting the float level and it seemed like it wasn't getting any fuel. Tried adjusting it more and it kept overflowing out the overflow.

And then the float bowl pin flew out when I went to pull it out and I lost it!

Ordered a new one. Just waiting on shipping.

New front tire and tube should be here tomorrow

my old yz 250 worked great under normal conditions, but when she started to run out of gas (left petcock closed one time) she would start revving and not shut off like you said. when you are driving thats terrifying. its caused by some kind of air leak i think. never did diagnose it.

good luck, post some pics please :)

Edited by buzzard111

Grab yourself a manual and set the float correctly rather than just guessing, it will tell you so much and help you not to break expensive and somewhat hard to find parts.

Trying to get this one running ima budget.

Already blew $55 on a new front tire that should be here tomorrow.

I know how to set the float-i just dont know the exact specs for this bike.

Just need to figure out the float height and ill be good to go.

Seems to run good until it drains the float out and revs up high.

Once I get the new float pin I ordered in the mail ($8 for a damn pin) ill readjust it again (after hopefully finding the specs online)

I know how to set the float-i just dont know the exact specs for this bike.

Just need to figure out the float height and ill be good to go.



A service manual will tell you this and will save you money since your on a budget.  Just did a quick search and there are factory and clymer manuals for under $30 at various places.

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